Applications of SQUID Microscopy in Bio-Magnetism

Outline

Cryostat Design

Dewar Tail

Retractable Pickup Coil

SQUID Microscope - Scanning Stage

SQUID Setup

Sensor Design - Tangential Field

Double-Loop SQUID

Field Sensitivity of LTS-SQUID with integrated 0.5 mm pickup loop

Pickup Coil

Field Sensitivity

Field Sensitivity

Field Sensitivity

Wire Scan

Natural Remnant Magnetization - Basalt

Could we be Martian?Panspermia - Lives On!

Allan Hills Meteorite – ALH84001In collaboration J. Kirschvink, B. Weiss, H. Vali

Thermal Demagnetization – ALH84001

Thermal Demagnetization – ALH84001

ALH84001-Fusion Crust

ALH84001-Fusion Crust

Cardiac Electrophysiology

Do measurements of the magnetic field associated with bioelectric currents provide new or different information compared to measurements of the electric field?

The Difficulty with the Magnetocardiogram

Magnetically Silent Sources

Getting closer ...

Simplify the Problem ...

Langendorff perfused Isolated Rabbit Heart

Langendorff perfused Isolated Rabbit Heart

SQUID Closeup

MCG As a Function of Position

Cathodal Current Injection

Initiation of Action Currents

Propagation of Action Currents

Cardiac Bidomain

BioDomain – Equations - Current Injection

Layered Bidomain Model

Propagation of Action Currents

Anisotropy

Action Potential Propagation

Circular Action Potential

Propagation of Action Currents

Can we extract Data?

Experimental Setup - Optical Imaging

S2- Point Stimulation

Isochrones - left ventricular free wall

Isochrones - Apex

Now - Add some Twist

PPT Slide

Dipole Signature in St-segment

Answers

Future Developments

Questions

The Cardiac Depolarization Wave Front